PDFs are a widely used format. Macs, PCs, and Linux OS's can read them and print them. The fonts always show correctly, and they're easy. Not our fault that Acrobat Reader on the PC sucks. If you right click the link and choose to download it, it will download to your HD and you can open it from there. Acrobat Reader works much better if you're openning a local file rather than something over the net.
Macs, well, they handle them seamlessly. Go us.
Linux, well, I'd hope anyone using linux would have a PDF reader installed.
If you really want, I'll post eps (encapsulated postscript) versions, or PS (postscript) versions... or even TIFFs. But like QEvil said, jpg's are going to be highly distorted when printed (they may look fine on your monitor, but printing something usually results in an image that has anywhere from 5-10x the resolution of a monitor). If someone really really wants another format, then let me know, I'll get you hooked up. But for now, PDFs are the best option.